The quality of the air supply of an inside of a building can often be contaminated with volatile organic compounds that are emissions from various sources that readily evaporate and mix with the air breathed by the occupants of the building. Volatile organic compounds are emitted from a variety of organic and inorganic materials including, for example: photocopiers, laser printers, dusts, cleaning fluid detergents, carpet emissions, furniture glues and paints, carpet glues, polishes and adhesives, scents from perfumes, ventilation system contaminants, fungi and moulds from damp areas, etc. Fungi spore fragments are ultra-fine particles of diameter less than 0.01 mm, which are easily and deeply ingested into the lungs. Such particles can cause damage to the lungs. They are one of the major concerns in a building because they are capable of multiplying and carry resistant pathogens, viruses and bacteria. Not only do fungi spores and spore fragments float in the air, but they collect on surfaces such as ceiling tiles where they can grow into a large biomass waiting for a triggering event to be released into the air.
Poor indoor air quality is responsible for a number of health problems, collectively known as Sick Building Syndrome. Such health problems include dryness and irritation of the eyes, nose and throat; difficulty concentrating on mental tasks; headache, fatigue and drowsiness; shortness of breath, itchy and dry skin; hypersensitivity and allergies. Illnesses from building related causes frequently affect the respiratory system. Flu-like symptoms such as fever, chills and shortness of breath, wheezing and fatigue frequently occur. In fact Legionnaires Disease is a building related disease caused by bacteria. Studies have shown that work productivity can rise by as much as 10% if the indoor air is clean and healthful.
Any substance used to treat building air must be safe for the occupants and at the same time have anti-microbial capabilities, which last a relatively long time. Essential oils are volatile oils distilled or extracted from plants such as thyme, lemongrass, citrus, anise, clove, aniseed, roses lavendar, citronella, cedar leaf, cinnamon leaf, camphor, etc. Such oils have been used for various medicinal purposes, as antiseptics and disinfectants, as insecticides, as food flavorings, and as solvents. Because of their hydrophobic nature essential oils cannot easily be formulated into aqueous mixtures. U.S. Pat. No. 5,403,587 issued to McCue et al. discloses that such oils can be solubilized or dispersed when combined in appropriate amounts with water and a solubilizing or dispersing agent and used for their anti-microbial properties. However, no studies have been done on the reduction in effectiveness of the essential oil caused by the carrier and surfactant or spreading agent.